Hermetic optical component packaging to date has employed metallic cans into which are disposed optoelectronic devices and with connections made to optical fibers. Typically, the active optoelectronic device is mounted on a submount and the submount is bonded to a metal package. Wire bonds are used to make electrical connections to wire pins which extend from a metal header. A hermetic seam seal is used to bond a metal cap to the header. Generally, the caps are lensed with a ball lens or have an ultra flat glass window or a cap with an optical fiber pigtail.
Lensed cap assemblies are commonly used in an active device amount (ADM) to effect coupling to an optical fiber. Typically, a mating connector containing an optical fiber is attached to the ADM. It is necessary to actively align the ADM and the fiber to the subassembly and then secure the assembly by welding, epoxy or soldering. This is a labor intensive procedure and furthermore there is a yield loss associated with the securing procedure, high costs associated with the packaging and an inherent complexity of the final assembly. All these factors singly and combined result in a high cost end product. Additionally, these assemblies tend to be bulky and are not readily encapsulable to form standard IC type packages.
As discussed in applicants' above-mentioned prior application Ser. No. 08/217,516, metallized fibers, having relatively thin metal coatings, are disclosed in U.S. Pat. No. to 4,033,668 to Presby. Bonding to another fiber or to an optical device is effected by welding or soldering in the radial direction about the outer circumference of the metallized fiber. A separate housing is required to effect coupling between the optical device and the fiber consequently, such an arrangement requires active alignment of the fiber to the device which is inherently labor intensive and bulky in design. In another technique described in U.S. Pat. No. 4,669,820 to Ten Berge, a metallized fiber is disclosed which allows for fiber-fiber and fiber-device coupling by crimping the metallized fiber. Such a technique effects fiber-device coupling via a lens. This is accomplished by disposing the fiber needle and the lens at opposite ends of a metal sleeve. Light from a laser is impingent on the lens for coupling to the fiber.
It is desirable to effect an accurate alignment between a fiber optic waveguide and a device without the aforementioned costs or complexities in assembly. The connector assembly described in applicants' aforementioned application Ser. No. 08/217,516, accomplishes this result.
However, a need in the art also exists for a submount for the active or passive optical device which hermetically encloses the optical device and the associated end of the optical fiber, in order to provide a sealed component package which is surface mountable and permits plastic overmolding. In the case of an active optical device (optoelectronic device) there is a need for a mount which provides good heat dissipation for the optoelectronic device in order to minimize temperature rise therein, and the ability to make electrical connections through the submount while maintaining hermeticity.